Southwest Hydrology: The Resource of Semi-Arid Hydrology Volume 4 Number 2

Home Browse Search

and other contaminants that tend to collect in the thermocline. In addition, SNWA will begin construction this spring of a bypass pipeline from its second intake to compensate for reduced intake capacity caused by lower lake levels. MWD Diversifies Since the 1988 -92 drought, Metropolitan Water District of Southern California (MWD) has initiated a series of programs designed to promote a more diversified water portfolio, improve system flexibility, and increase storage capability within and outside of its service area to capture water for subsequent use. In an effort to help maintain reservoir levels in Lake Mead, MWD elected not to order surplus water from the Colorado River in 2003 and 2004, despite its availability under the Interim Surplus Guidelines. Water conservation, recycling and contaminated water recovery, and desalting of brackish and saline water are methods being increasingly used to meet MWD's water needs during the current drought. Arizona Banks Water for Nevada Although Arizona had previously agreed to use "best efforts" to store 1.2 million acre -feet of Colorado River water for SNWA pursuant to a 2001 agreement, the drought has caused Nevada to seek and obtain a modification of the agreement to "guarantee" storage of water starting immediately. In exchange for guaranteeing storage of unused Colorado River water in Arizona's aquifers, SNWA will pay $100 million over the actual cost to bank this water (see Nevada and Arizona article, page 13). This money will be used to improve recovery options and supplement local supplies in Arizona. Shortage Criteria Under Development The seven basin states continue to work in cooperation with the federal government to develop strategies for dealing with reduced supplies caused by the drought. They have four objectives: agree to shortage criteria, improve the efficiency of water deliveries, provide for conjunctive management between Mead and Powell, and identify opportunities to reduce deliveries to Mexico under the 1944 treaty. While this strategy will not eliminate all problems caused by the drought, it will mitigate some of the impacts of declining reservoirs. Better Management, Increased Flexibility Although the hydrologic conditions that fostered recent agreements between the Lower Basin states and the Department of the Interior have radically changed, a critical framework was put in place that allows for better management of the river system. California and Nevada are continuing to develop internal water supplies that will reduce their dependence on the Colorado River and provide more flexibility in their water budgets. These agreements also established a clear precedent for cooperation among the states for solving the problems that confront them. However, if the drought continues, the Bureau anticipates that normal deliveries to the Lower Basin states could be See Lower Basin, page 38 Central Arizona Project Sustaining Our Desert b e www.cap- az.com Luke I'hrlu!!n storage' resenvir March /April 2005 • Southwest Hydrology • 23